Loading...
1/**************************************************************************
2 *
3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31#ifndef _TTM_BO_API_H_
32#define _TTM_BO_API_H_
33
34#include <drm/drm_gem.h>
35#include <drm/drm_vma_manager.h>
36#include <linux/kref.h>
37#include <linux/list.h>
38#include <linux/wait.h>
39#include <linux/mutex.h>
40#include <linux/mm.h>
41#include <linux/bitmap.h>
42#include <linux/dma-resv.h>
43
44#include "ttm_resource.h"
45
46struct ttm_global;
47
48struct ttm_device;
49
50struct iosys_map;
51
52struct drm_mm_node;
53
54struct ttm_placement;
55
56struct ttm_place;
57
58/**
59 * enum ttm_bo_type
60 *
61 * @ttm_bo_type_device: These are 'normal' buffers that can
62 * be mmapped by user space. Each of these bos occupy a slot in the
63 * device address space, that can be used for normal vm operations.
64 *
65 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
66 * but they cannot be accessed from user-space. For kernel-only use.
67 *
68 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
69 * driver.
70 */
71
72enum ttm_bo_type {
73 ttm_bo_type_device,
74 ttm_bo_type_kernel,
75 ttm_bo_type_sg
76};
77
78struct ttm_tt;
79
80/**
81 * struct ttm_buffer_object
82 *
83 * @base: drm_gem_object superclass data.
84 * @bdev: Pointer to the buffer object device structure.
85 * @type: The bo type.
86 * @page_alignment: Page alignment.
87 * @destroy: Destruction function. If NULL, kfree is used.
88 * @num_pages: Actual number of pages.
89 * @kref: Reference count of this buffer object. When this refcount reaches
90 * zero, the object is destroyed or put on the delayed delete list.
91 * @mem: structure describing current placement.
92 * @ttm: TTM structure holding system pages.
93 * @evicted: Whether the object was evicted without user-space knowing.
94 * @deleted: True if the object is only a zombie and already deleted.
95 * @ddestroy: List head for the delayed destroy list.
96 * @swap: List head for swap LRU list.
97 * @offset: The current GPU offset, which can have different meanings
98 * depending on the memory type. For SYSTEM type memory, it should be 0.
99 * @cur_placement: Hint of current placement.
100 *
101 * Base class for TTM buffer object, that deals with data placement and CPU
102 * mappings. GPU mappings are really up to the driver, but for simpler GPUs
103 * the driver can usually use the placement offset @offset directly as the
104 * GPU virtual address. For drivers implementing multiple
105 * GPU memory manager contexts, the driver should manage the address space
106 * in these contexts separately and use these objects to get the correct
107 * placement and caching for these GPU maps. This makes it possible to use
108 * these objects for even quite elaborate memory management schemes.
109 * The destroy member, the API visibility of this object makes it possible
110 * to derive driver specific types.
111 */
112
113struct ttm_buffer_object {
114 struct drm_gem_object base;
115
116 /**
117 * Members constant at init.
118 */
119
120 struct ttm_device *bdev;
121 enum ttm_bo_type type;
122 uint32_t page_alignment;
123 void (*destroy) (struct ttm_buffer_object *);
124
125 /**
126 * Members not needing protection.
127 */
128 struct kref kref;
129
130 /**
131 * Members protected by the bo::resv::reserved lock.
132 */
133
134 struct ttm_resource *resource;
135 struct ttm_tt *ttm;
136 bool deleted;
137 struct ttm_lru_bulk_move *bulk_move;
138
139 /**
140 * Members protected by the bdev::lru_lock.
141 */
142
143 struct list_head ddestroy;
144
145 /**
146 * Members protected by a bo reservation.
147 */
148
149 unsigned priority;
150 unsigned pin_count;
151
152 /**
153 * Special members that are protected by the reserve lock
154 * and the bo::lock when written to. Can be read with
155 * either of these locks held.
156 */
157
158 struct sg_table *sg;
159};
160
161/**
162 * struct ttm_bo_kmap_obj
163 *
164 * @virtual: The current kernel virtual address.
165 * @page: The page when kmap'ing a single page.
166 * @bo_kmap_type: Type of bo_kmap.
167 *
168 * Object describing a kernel mapping. Since a TTM bo may be located
169 * in various memory types with various caching policies, the
170 * mapping can either be an ioremap, a vmap, a kmap or part of a
171 * premapped region.
172 */
173
174#define TTM_BO_MAP_IOMEM_MASK 0x80
175struct ttm_bo_kmap_obj {
176 void *virtual;
177 struct page *page;
178 enum {
179 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
180 ttm_bo_map_vmap = 2,
181 ttm_bo_map_kmap = 3,
182 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
183 } bo_kmap_type;
184 struct ttm_buffer_object *bo;
185};
186
187/**
188 * struct ttm_operation_ctx
189 *
190 * @interruptible: Sleep interruptible if sleeping.
191 * @no_wait_gpu: Return immediately if the GPU is busy.
192 * @gfp_retry_mayfail: Set the __GFP_RETRY_MAYFAIL when allocation pages.
193 * @allow_res_evict: Allow eviction of reserved BOs. Can be used when multiple
194 * BOs share the same reservation object.
195 * @force_alloc: Don't check the memory account during suspend or CPU page
196 * faults. Should only be used by TTM internally.
197 * @resv: Reservation object to allow reserved evictions with.
198 *
199 * Context for TTM operations like changing buffer placement or general memory
200 * allocation.
201 */
202struct ttm_operation_ctx {
203 bool interruptible;
204 bool no_wait_gpu;
205 bool gfp_retry_mayfail;
206 bool allow_res_evict;
207 bool force_alloc;
208 struct dma_resv *resv;
209 uint64_t bytes_moved;
210};
211
212/**
213 * ttm_bo_get - reference a struct ttm_buffer_object
214 *
215 * @bo: The buffer object.
216 */
217static inline void ttm_bo_get(struct ttm_buffer_object *bo)
218{
219 kref_get(&bo->kref);
220}
221
222/**
223 * ttm_bo_get_unless_zero - reference a struct ttm_buffer_object unless
224 * its refcount has already reached zero.
225 * @bo: The buffer object.
226 *
227 * Used to reference a TTM buffer object in lookups where the object is removed
228 * from the lookup structure during the destructor and for RCU lookups.
229 *
230 * Returns: @bo if the referencing was successful, NULL otherwise.
231 */
232static inline __must_check struct ttm_buffer_object *
233ttm_bo_get_unless_zero(struct ttm_buffer_object *bo)
234{
235 if (!kref_get_unless_zero(&bo->kref))
236 return NULL;
237 return bo;
238}
239
240/**
241 * ttm_bo_wait - wait for buffer idle.
242 *
243 * @bo: The buffer object.
244 * @interruptible: Use interruptible wait.
245 * @no_wait: Return immediately if buffer is busy.
246 *
247 * This function must be called with the bo::mutex held, and makes
248 * sure any previous rendering to the buffer is completed.
249 * Note: It might be necessary to block validations before the
250 * wait by reserving the buffer.
251 * Returns -EBUSY if no_wait is true and the buffer is busy.
252 * Returns -ERESTARTSYS if interrupted by a signal.
253 */
254int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait);
255
256static inline int ttm_bo_wait_ctx(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx)
257{
258 return ttm_bo_wait(bo, ctx->interruptible, ctx->no_wait_gpu);
259}
260
261/**
262 * ttm_bo_validate
263 *
264 * @bo: The buffer object.
265 * @placement: Proposed placement for the buffer object.
266 * @ctx: validation parameters.
267 *
268 * Changes placement and caching policy of the buffer object
269 * according proposed placement.
270 * Returns
271 * -EINVAL on invalid proposed placement.
272 * -ENOMEM on out-of-memory condition.
273 * -EBUSY if no_wait is true and buffer busy.
274 * -ERESTARTSYS if interrupted by a signal.
275 */
276int ttm_bo_validate(struct ttm_buffer_object *bo,
277 struct ttm_placement *placement,
278 struct ttm_operation_ctx *ctx);
279
280/**
281 * ttm_bo_put
282 *
283 * @bo: The buffer object.
284 *
285 * Unreference a buffer object.
286 */
287void ttm_bo_put(struct ttm_buffer_object *bo);
288
289void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo);
290void ttm_bo_set_bulk_move(struct ttm_buffer_object *bo,
291 struct ttm_lru_bulk_move *bulk);
292
293/**
294 * ttm_bo_lock_delayed_workqueue
295 *
296 * Prevent the delayed workqueue from running.
297 * Returns
298 * True if the workqueue was queued at the time
299 */
300int ttm_bo_lock_delayed_workqueue(struct ttm_device *bdev);
301
302/**
303 * ttm_bo_unlock_delayed_workqueue
304 *
305 * Allows the delayed workqueue to run.
306 */
307void ttm_bo_unlock_delayed_workqueue(struct ttm_device *bdev, int resched);
308
309/**
310 * ttm_bo_eviction_valuable
311 *
312 * @bo: The buffer object to evict
313 * @place: the placement we need to make room for
314 *
315 * Check if it is valuable to evict the BO to make room for the given placement.
316 */
317bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
318 const struct ttm_place *place);
319
320int ttm_bo_init_reserved(struct ttm_device *bdev, struct ttm_buffer_object *bo,
321 enum ttm_bo_type type, struct ttm_placement *placement,
322 uint32_t alignment, struct ttm_operation_ctx *ctx,
323 struct sg_table *sg, struct dma_resv *resv,
324 void (*destroy) (struct ttm_buffer_object *));
325int ttm_bo_init_validate(struct ttm_device *bdev, struct ttm_buffer_object *bo,
326 enum ttm_bo_type type, struct ttm_placement *placement,
327 uint32_t alignment, bool interruptible,
328 struct sg_table *sg, struct dma_resv *resv,
329 void (*destroy) (struct ttm_buffer_object *));
330
331/**
332 * ttm_kmap_obj_virtual
333 *
334 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
335 * @is_iomem: Pointer to an integer that on return indicates 1 if the
336 * virtual map is io memory, 0 if normal memory.
337 *
338 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
339 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
340 * that should strictly be accessed by the iowriteXX() and similar functions.
341 */
342static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
343 bool *is_iomem)
344{
345 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
346 return map->virtual;
347}
348
349/**
350 * ttm_bo_kmap
351 *
352 * @bo: The buffer object.
353 * @start_page: The first page to map.
354 * @num_pages: Number of pages to map.
355 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
356 *
357 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
358 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
359 * used to obtain a virtual address to the data.
360 *
361 * Returns
362 * -ENOMEM: Out of memory.
363 * -EINVAL: Invalid range.
364 */
365int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
366 unsigned long num_pages, struct ttm_bo_kmap_obj *map);
367
368/**
369 * ttm_bo_kunmap
370 *
371 * @map: Object describing the map to unmap.
372 *
373 * Unmaps a kernel map set up by ttm_bo_kmap.
374 */
375void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
376
377/**
378 * ttm_bo_vmap
379 *
380 * @bo: The buffer object.
381 * @map: pointer to a struct iosys_map representing the map.
382 *
383 * Sets up a kernel virtual mapping, using ioremap or vmap to the
384 * data in the buffer object. The parameter @map returns the virtual
385 * address as struct iosys_map. Unmap the buffer with ttm_bo_vunmap().
386 *
387 * Returns
388 * -ENOMEM: Out of memory.
389 * -EINVAL: Invalid range.
390 */
391int ttm_bo_vmap(struct ttm_buffer_object *bo, struct iosys_map *map);
392
393/**
394 * ttm_bo_vunmap
395 *
396 * @bo: The buffer object.
397 * @map: Object describing the map to unmap.
398 *
399 * Unmaps a kernel map set up by ttm_bo_vmap().
400 */
401void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct iosys_map *map);
402
403/**
404 * ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object.
405 *
406 * @vma: vma as input from the fbdev mmap method.
407 * @bo: The bo backing the address space.
408 *
409 * Maps a buffer object.
410 */
411int ttm_bo_mmap_obj(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
412
413/**
414 * ttm_bo_io
415 *
416 * @bdev: Pointer to the struct ttm_device.
417 * @filp: Pointer to the struct file attempting to read / write.
418 * @wbuf: User-space pointer to address of buffer to write. NULL on read.
419 * @rbuf: User-space pointer to address of buffer to read into.
420 * Null on write.
421 * @count: Number of bytes to read / write.
422 * @f_pos: Pointer to current file position.
423 * @write: 1 for read, 0 for write.
424 *
425 * This function implements read / write into ttm buffer objects, and is
426 * intended to
427 * be called from the fops::read and fops::write method.
428 * Returns:
429 * See man (2) write, man(2) read. In particular,
430 * the function may return -ERESTARTSYS if
431 * interrupted by a signal.
432 */
433ssize_t ttm_bo_io(struct ttm_device *bdev, struct file *filp,
434 const char __user *wbuf, char __user *rbuf,
435 size_t count, loff_t *f_pos, bool write);
436
437int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx,
438 gfp_t gfp_flags);
439
440void ttm_bo_pin(struct ttm_buffer_object *bo);
441void ttm_bo_unpin(struct ttm_buffer_object *bo);
442
443int ttm_mem_evict_first(struct ttm_device *bdev,
444 struct ttm_resource_manager *man,
445 const struct ttm_place *place,
446 struct ttm_operation_ctx *ctx,
447 struct ww_acquire_ctx *ticket);
448
449/* Default number of pre-faulted pages in the TTM fault handler */
450#define TTM_BO_VM_NUM_PREFAULT 16
451
452vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
453 struct vm_fault *vmf);
454
455vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
456 pgprot_t prot,
457 pgoff_t num_prefault);
458
459vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf);
460
461void ttm_bo_vm_open(struct vm_area_struct *vma);
462
463void ttm_bo_vm_close(struct vm_area_struct *vma);
464
465int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
466 void *buf, int len, int write);
467bool ttm_bo_delayed_delete(struct ttm_device *bdev, bool remove_all);
468
469vm_fault_t ttm_bo_vm_dummy_page(struct vm_fault *vmf, pgprot_t prot);
470
471#endif
1/**************************************************************************
2 *
3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31#ifndef _TTM_BO_API_H_
32#define _TTM_BO_API_H_
33
34#include <drm/drm_hashtab.h>
35#include <drm/drm_vma_manager.h>
36#include <linux/kref.h>
37#include <linux/list.h>
38#include <linux/wait.h>
39#include <linux/mutex.h>
40#include <linux/mm.h>
41#include <linux/bitmap.h>
42#include <linux/reservation.h>
43
44struct ttm_bo_global;
45
46struct ttm_bo_device;
47
48struct drm_mm_node;
49
50struct ttm_placement;
51
52struct ttm_place;
53
54/**
55 * struct ttm_bus_placement
56 *
57 * @addr: mapped virtual address
58 * @base: bus base address
59 * @is_iomem: is this io memory ?
60 * @size: size in byte
61 * @offset: offset from the base address
62 * @io_reserved_vm: The VM system has a refcount in @io_reserved_count
63 * @io_reserved_count: Refcounting the numbers of callers to ttm_mem_io_reserve
64 *
65 * Structure indicating the bus placement of an object.
66 */
67struct ttm_bus_placement {
68 void *addr;
69 phys_addr_t base;
70 unsigned long size;
71 unsigned long offset;
72 bool is_iomem;
73 bool io_reserved_vm;
74 uint64_t io_reserved_count;
75};
76
77
78/**
79 * struct ttm_mem_reg
80 *
81 * @mm_node: Memory manager node.
82 * @size: Requested size of memory region.
83 * @num_pages: Actual size of memory region in pages.
84 * @page_alignment: Page alignment.
85 * @placement: Placement flags.
86 * @bus: Placement on io bus accessible to the CPU
87 *
88 * Structure indicating the placement and space resources used by a
89 * buffer object.
90 */
91
92struct ttm_mem_reg {
93 void *mm_node;
94 unsigned long start;
95 unsigned long size;
96 unsigned long num_pages;
97 uint32_t page_alignment;
98 uint32_t mem_type;
99 uint32_t placement;
100 struct ttm_bus_placement bus;
101};
102
103/**
104 * enum ttm_bo_type
105 *
106 * @ttm_bo_type_device: These are 'normal' buffers that can
107 * be mmapped by user space. Each of these bos occupy a slot in the
108 * device address space, that can be used for normal vm operations.
109 *
110 * @ttm_bo_type_kernel: These buffers are like ttm_bo_type_device buffers,
111 * but they cannot be accessed from user-space. For kernel-only use.
112 *
113 * @ttm_bo_type_sg: Buffer made from dmabuf sg table shared with another
114 * driver.
115 */
116
117enum ttm_bo_type {
118 ttm_bo_type_device,
119 ttm_bo_type_kernel,
120 ttm_bo_type_sg
121};
122
123struct ttm_tt;
124
125/**
126 * struct ttm_buffer_object
127 *
128 * @bdev: Pointer to the buffer object device structure.
129 * @type: The bo type.
130 * @destroy: Destruction function. If NULL, kfree is used.
131 * @num_pages: Actual number of pages.
132 * @acc_size: Accounted size for this object.
133 * @kref: Reference count of this buffer object. When this refcount reaches
134 * zero, the object is put on the delayed delete list.
135 * @list_kref: List reference count of this buffer object. This member is
136 * used to avoid destruction while the buffer object is still on a list.
137 * Lru lists may keep one refcount, the delayed delete list, and kref != 0
138 * keeps one refcount. When this refcount reaches zero,
139 * the object is destroyed.
140 * @mem: structure describing current placement.
141 * @persistent_swap_storage: Usually the swap storage is deleted for buffers
142 * pinned in physical memory. If this behaviour is not desired, this member
143 * holds a pointer to a persistent shmem object.
144 * @ttm: TTM structure holding system pages.
145 * @evicted: Whether the object was evicted without user-space knowing.
146 * @cpu_writes: For synchronization. Number of cpu writers.
147 * @lru: List head for the lru list.
148 * @ddestroy: List head for the delayed destroy list.
149 * @swap: List head for swap LRU list.
150 * @moving: Fence set when BO is moving
151 * @vma_node: Address space manager node.
152 * @offset: The current GPU offset, which can have different meanings
153 * depending on the memory type. For SYSTEM type memory, it should be 0.
154 * @cur_placement: Hint of current placement.
155 * @wu_mutex: Wait unreserved mutex.
156 *
157 * Base class for TTM buffer object, that deals with data placement and CPU
158 * mappings. GPU mappings are really up to the driver, but for simpler GPUs
159 * the driver can usually use the placement offset @offset directly as the
160 * GPU virtual address. For drivers implementing multiple
161 * GPU memory manager contexts, the driver should manage the address space
162 * in these contexts separately and use these objects to get the correct
163 * placement and caching for these GPU maps. This makes it possible to use
164 * these objects for even quite elaborate memory management schemes.
165 * The destroy member, the API visibility of this object makes it possible
166 * to derive driver specific types.
167 */
168
169struct ttm_buffer_object {
170 /**
171 * Members constant at init.
172 */
173
174 struct ttm_bo_device *bdev;
175 enum ttm_bo_type type;
176 void (*destroy) (struct ttm_buffer_object *);
177 unsigned long num_pages;
178 size_t acc_size;
179
180 /**
181 * Members not needing protection.
182 */
183
184 struct kref kref;
185 struct kref list_kref;
186
187 /**
188 * Members protected by the bo::resv::reserved lock.
189 */
190
191 struct ttm_mem_reg mem;
192 struct file *persistent_swap_storage;
193 struct ttm_tt *ttm;
194 bool evicted;
195
196 /**
197 * Members protected by the bo::reserved lock only when written to.
198 */
199
200 atomic_t cpu_writers;
201
202 /**
203 * Members protected by the bdev::lru_lock.
204 */
205
206 struct list_head lru;
207 struct list_head ddestroy;
208 struct list_head swap;
209 struct list_head io_reserve_lru;
210
211 /**
212 * Members protected by a bo reservation.
213 */
214
215 struct dma_fence *moving;
216
217 struct drm_vma_offset_node vma_node;
218
219 unsigned priority;
220
221 /**
222 * Special members that are protected by the reserve lock
223 * and the bo::lock when written to. Can be read with
224 * either of these locks held.
225 */
226
227 uint64_t offset; /* GPU address space is independent of CPU word size */
228
229 struct sg_table *sg;
230
231 struct reservation_object *resv;
232 struct reservation_object ttm_resv;
233 struct mutex wu_mutex;
234};
235
236/**
237 * struct ttm_bo_kmap_obj
238 *
239 * @virtual: The current kernel virtual address.
240 * @page: The page when kmap'ing a single page.
241 * @bo_kmap_type: Type of bo_kmap.
242 *
243 * Object describing a kernel mapping. Since a TTM bo may be located
244 * in various memory types with various caching policies, the
245 * mapping can either be an ioremap, a vmap, a kmap or part of a
246 * premapped region.
247 */
248
249#define TTM_BO_MAP_IOMEM_MASK 0x80
250struct ttm_bo_kmap_obj {
251 void *virtual;
252 struct page *page;
253 enum {
254 ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
255 ttm_bo_map_vmap = 2,
256 ttm_bo_map_kmap = 3,
257 ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
258 } bo_kmap_type;
259 struct ttm_buffer_object *bo;
260};
261
262/**
263 * struct ttm_operation_ctx
264 *
265 * @interruptible: Sleep interruptible if sleeping.
266 * @no_wait_gpu: Return immediately if the GPU is busy.
267 * @resv: Reservation object to allow reserved evictions with.
268 * @flags: Including the following flags
269 *
270 * Context for TTM operations like changing buffer placement or general memory
271 * allocation.
272 */
273struct ttm_operation_ctx {
274 bool interruptible;
275 bool no_wait_gpu;
276 struct reservation_object *resv;
277 uint64_t bytes_moved;
278 uint32_t flags;
279};
280
281/* Allow eviction of reserved BOs */
282#define TTM_OPT_FLAG_ALLOW_RES_EVICT 0x1
283/* when serving page fault or suspend, allow alloc anyway */
284#define TTM_OPT_FLAG_FORCE_ALLOC 0x2
285
286/**
287 * ttm_bo_reference - reference a struct ttm_buffer_object
288 *
289 * @bo: The buffer object.
290 *
291 * Returns a refcounted pointer to a buffer object.
292 */
293
294static inline struct ttm_buffer_object *
295ttm_bo_reference(struct ttm_buffer_object *bo)
296{
297 kref_get(&bo->kref);
298 return bo;
299}
300
301/**
302 * ttm_bo_wait - wait for buffer idle.
303 *
304 * @bo: The buffer object.
305 * @interruptible: Use interruptible wait.
306 * @no_wait: Return immediately if buffer is busy.
307 *
308 * This function must be called with the bo::mutex held, and makes
309 * sure any previous rendering to the buffer is completed.
310 * Note: It might be necessary to block validations before the
311 * wait by reserving the buffer.
312 * Returns -EBUSY if no_wait is true and the buffer is busy.
313 * Returns -ERESTARTSYS if interrupted by a signal.
314 */
315int ttm_bo_wait(struct ttm_buffer_object *bo, bool interruptible, bool no_wait);
316
317/**
318 * ttm_bo_mem_compat - Check if proposed placement is compatible with a bo
319 *
320 * @placement: Return immediately if buffer is busy.
321 * @mem: The struct ttm_mem_reg indicating the region where the bo resides
322 * @new_flags: Describes compatible placement found
323 *
324 * Returns true if the placement is compatible
325 */
326bool ttm_bo_mem_compat(struct ttm_placement *placement, struct ttm_mem_reg *mem,
327 uint32_t *new_flags);
328
329/**
330 * ttm_bo_validate
331 *
332 * @bo: The buffer object.
333 * @placement: Proposed placement for the buffer object.
334 * @ctx: validation parameters.
335 *
336 * Changes placement and caching policy of the buffer object
337 * according proposed placement.
338 * Returns
339 * -EINVAL on invalid proposed placement.
340 * -ENOMEM on out-of-memory condition.
341 * -EBUSY if no_wait is true and buffer busy.
342 * -ERESTARTSYS if interrupted by a signal.
343 */
344int ttm_bo_validate(struct ttm_buffer_object *bo,
345 struct ttm_placement *placement,
346 struct ttm_operation_ctx *ctx);
347
348/**
349 * ttm_bo_unref
350 *
351 * @bo: The buffer object.
352 *
353 * Unreference and clear a pointer to a buffer object.
354 */
355void ttm_bo_unref(struct ttm_buffer_object **bo);
356
357/**
358 * ttm_bo_add_to_lru
359 *
360 * @bo: The buffer object.
361 *
362 * Add this bo to the relevant mem type lru and, if it's backed by
363 * system pages (ttms) to the swap list.
364 * This function must be called with struct ttm_bo_global::lru_lock held, and
365 * is typically called immediately prior to unreserving a bo.
366 */
367void ttm_bo_add_to_lru(struct ttm_buffer_object *bo);
368
369/**
370 * ttm_bo_del_from_lru
371 *
372 * @bo: The buffer object.
373 *
374 * Remove this bo from all lru lists used to lookup and reserve an object.
375 * This function must be called with struct ttm_bo_global::lru_lock held,
376 * and is usually called just immediately after the bo has been reserved to
377 * avoid recursive reservation from lru lists.
378 */
379void ttm_bo_del_from_lru(struct ttm_buffer_object *bo);
380
381/**
382 * ttm_bo_move_to_lru_tail
383 *
384 * @bo: The buffer object.
385 *
386 * Move this BO to the tail of all lru lists used to lookup and reserve an
387 * object. This function must be called with struct ttm_bo_global::lru_lock
388 * held, and is used to make a BO less likely to be considered for eviction.
389 */
390void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo);
391
392/**
393 * ttm_bo_lock_delayed_workqueue
394 *
395 * Prevent the delayed workqueue from running.
396 * Returns
397 * True if the workqueue was queued at the time
398 */
399int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev);
400
401/**
402 * ttm_bo_unlock_delayed_workqueue
403 *
404 * Allows the delayed workqueue to run.
405 */
406void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched);
407
408/**
409 * ttm_bo_eviction_valuable
410 *
411 * @bo: The buffer object to evict
412 * @place: the placement we need to make room for
413 *
414 * Check if it is valuable to evict the BO to make room for the given placement.
415 */
416bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
417 const struct ttm_place *place);
418
419/**
420 * ttm_bo_synccpu_write_grab
421 *
422 * @bo: The buffer object:
423 * @no_wait: Return immediately if buffer is busy.
424 *
425 * Synchronizes a buffer object for CPU RW access. This means
426 * command submission that affects the buffer will return -EBUSY
427 * until ttm_bo_synccpu_write_release is called.
428 *
429 * Returns
430 * -EBUSY if the buffer is busy and no_wait is true.
431 * -ERESTARTSYS if interrupted by a signal.
432 */
433int ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait);
434
435/**
436 * ttm_bo_synccpu_write_release:
437 *
438 * @bo : The buffer object.
439 *
440 * Releases a synccpu lock.
441 */
442void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo);
443
444/**
445 * ttm_bo_acc_size
446 *
447 * @bdev: Pointer to a ttm_bo_device struct.
448 * @bo_size: size of the buffer object in byte.
449 * @struct_size: size of the structure holding buffer object datas
450 *
451 * Returns size to account for a buffer object
452 */
453size_t ttm_bo_acc_size(struct ttm_bo_device *bdev,
454 unsigned long bo_size,
455 unsigned struct_size);
456size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
457 unsigned long bo_size,
458 unsigned struct_size);
459
460/**
461 * ttm_bo_init_reserved
462 *
463 * @bdev: Pointer to a ttm_bo_device struct.
464 * @bo: Pointer to a ttm_buffer_object to be initialized.
465 * @size: Requested size of buffer object.
466 * @type: Requested type of buffer object.
467 * @flags: Initial placement flags.
468 * @page_alignment: Data alignment in pages.
469 * @ctx: TTM operation context for memory allocation.
470 * @acc_size: Accounted size for this object.
471 * @resv: Pointer to a reservation_object, or NULL to let ttm allocate one.
472 * @destroy: Destroy function. Use NULL for kfree().
473 *
474 * This function initializes a pre-allocated struct ttm_buffer_object.
475 * As this object may be part of a larger structure, this function,
476 * together with the @destroy function,
477 * enables driver-specific objects derived from a ttm_buffer_object.
478 *
479 * On successful return, the caller owns an object kref to @bo. The kref and
480 * list_kref are usually set to 1, but note that in some situations, other
481 * tasks may already be holding references to @bo as well.
482 * Furthermore, if resv == NULL, the buffer's reservation lock will be held,
483 * and it is the caller's responsibility to call ttm_bo_unreserve.
484 *
485 * If a failure occurs, the function will call the @destroy function, or
486 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
487 * illegal and will likely cause memory corruption.
488 *
489 * Returns
490 * -ENOMEM: Out of memory.
491 * -EINVAL: Invalid placement flags.
492 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
493 */
494
495int ttm_bo_init_reserved(struct ttm_bo_device *bdev,
496 struct ttm_buffer_object *bo,
497 unsigned long size,
498 enum ttm_bo_type type,
499 struct ttm_placement *placement,
500 uint32_t page_alignment,
501 struct ttm_operation_ctx *ctx,
502 size_t acc_size,
503 struct sg_table *sg,
504 struct reservation_object *resv,
505 void (*destroy) (struct ttm_buffer_object *));
506
507/**
508 * ttm_bo_init
509 *
510 * @bdev: Pointer to a ttm_bo_device struct.
511 * @bo: Pointer to a ttm_buffer_object to be initialized.
512 * @size: Requested size of buffer object.
513 * @type: Requested type of buffer object.
514 * @flags: Initial placement flags.
515 * @page_alignment: Data alignment in pages.
516 * @interruptible: If needing to sleep to wait for GPU resources,
517 * sleep interruptible.
518 * pinned in physical memory. If this behaviour is not desired, this member
519 * holds a pointer to a persistent shmem object. Typically, this would
520 * point to the shmem object backing a GEM object if TTM is used to back a
521 * GEM user interface.
522 * @acc_size: Accounted size for this object.
523 * @resv: Pointer to a reservation_object, or NULL to let ttm allocate one.
524 * @destroy: Destroy function. Use NULL for kfree().
525 *
526 * This function initializes a pre-allocated struct ttm_buffer_object.
527 * As this object may be part of a larger structure, this function,
528 * together with the @destroy function,
529 * enables driver-specific objects derived from a ttm_buffer_object.
530 *
531 * On successful return, the caller owns an object kref to @bo. The kref and
532 * list_kref are usually set to 1, but note that in some situations, other
533 * tasks may already be holding references to @bo as well.
534 *
535 * If a failure occurs, the function will call the @destroy function, or
536 * kfree() if @destroy is NULL. Thus, after a failure, dereferencing @bo is
537 * illegal and will likely cause memory corruption.
538 *
539 * Returns
540 * -ENOMEM: Out of memory.
541 * -EINVAL: Invalid placement flags.
542 * -ERESTARTSYS: Interrupted by signal while sleeping waiting for resources.
543 */
544int ttm_bo_init(struct ttm_bo_device *bdev, struct ttm_buffer_object *bo,
545 unsigned long size, enum ttm_bo_type type,
546 struct ttm_placement *placement,
547 uint32_t page_alignment, bool interrubtible, size_t acc_size,
548 struct sg_table *sg, struct reservation_object *resv,
549 void (*destroy) (struct ttm_buffer_object *));
550
551/**
552 * ttm_bo_create
553 *
554 * @bdev: Pointer to a ttm_bo_device struct.
555 * @size: Requested size of buffer object.
556 * @type: Requested type of buffer object.
557 * @placement: Initial placement.
558 * @page_alignment: Data alignment in pages.
559 * @interruptible: If needing to sleep while waiting for GPU resources,
560 * sleep interruptible.
561 * @p_bo: On successful completion *p_bo points to the created object.
562 *
563 * This function allocates a ttm_buffer_object, and then calls ttm_bo_init
564 * on that object. The destroy function is set to kfree().
565 * Returns
566 * -ENOMEM: Out of memory.
567 * -EINVAL: Invalid placement flags.
568 * -ERESTARTSYS: Interrupted by signal while waiting for resources.
569 */
570int ttm_bo_create(struct ttm_bo_device *bdev, unsigned long size,
571 enum ttm_bo_type type, struct ttm_placement *placement,
572 uint32_t page_alignment, bool interruptible,
573 struct ttm_buffer_object **p_bo);
574
575/**
576 * ttm_bo_init_mm
577 *
578 * @bdev: Pointer to a ttm_bo_device struct.
579 * @mem_type: The memory type.
580 * @p_size: size managed area in pages.
581 *
582 * Initialize a manager for a given memory type.
583 * Note: if part of driver firstopen, it must be protected from a
584 * potentially racing lastclose.
585 * Returns:
586 * -EINVAL: invalid size or memory type.
587 * -ENOMEM: Not enough memory.
588 * May also return driver-specified errors.
589 */
590int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
591 unsigned long p_size);
592
593/**
594 * ttm_bo_clean_mm
595 *
596 * @bdev: Pointer to a ttm_bo_device struct.
597 * @mem_type: The memory type.
598 *
599 * Take down a manager for a given memory type after first walking
600 * the LRU list to evict any buffers left alive.
601 *
602 * Normally, this function is part of lastclose() or unload(), and at that
603 * point there shouldn't be any buffers left created by user-space, since
604 * there should've been removed by the file descriptor release() method.
605 * However, before this function is run, make sure to signal all sync objects,
606 * and verify that the delayed delete queue is empty. The driver must also
607 * make sure that there are no NO_EVICT buffers present in this memory type
608 * when the call is made.
609 *
610 * If this function is part of a VT switch, the caller must make sure that
611 * there are no appications currently validating buffers before this
612 * function is called. The caller can do that by first taking the
613 * struct ttm_bo_device::ttm_lock in write mode.
614 *
615 * Returns:
616 * -EINVAL: invalid or uninitialized memory type.
617 * -EBUSY: There are still buffers left in this memory type.
618 */
619int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type);
620
621/**
622 * ttm_bo_evict_mm
623 *
624 * @bdev: Pointer to a ttm_bo_device struct.
625 * @mem_type: The memory type.
626 *
627 * Evicts all buffers on the lru list of the memory type.
628 * This is normally part of a VT switch or an
629 * out-of-memory-space-due-to-fragmentation handler.
630 * The caller must make sure that there are no other processes
631 * currently validating buffers, and can do that by taking the
632 * struct ttm_bo_device::ttm_lock in write mode.
633 *
634 * Returns:
635 * -EINVAL: Invalid or uninitialized memory type.
636 * -ERESTARTSYS: The call was interrupted by a signal while waiting to
637 * evict a buffer.
638 */
639int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type);
640
641/**
642 * ttm_kmap_obj_virtual
643 *
644 * @map: A struct ttm_bo_kmap_obj returned from ttm_bo_kmap.
645 * @is_iomem: Pointer to an integer that on return indicates 1 if the
646 * virtual map is io memory, 0 if normal memory.
647 *
648 * Returns the virtual address of a buffer object area mapped by ttm_bo_kmap.
649 * If *is_iomem is 1 on return, the virtual address points to an io memory area,
650 * that should strictly be accessed by the iowriteXX() and similar functions.
651 */
652static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
653 bool *is_iomem)
654{
655 *is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
656 return map->virtual;
657}
658
659/**
660 * ttm_bo_kmap
661 *
662 * @bo: The buffer object.
663 * @start_page: The first page to map.
664 * @num_pages: Number of pages to map.
665 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
666 *
667 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
668 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
669 * used to obtain a virtual address to the data.
670 *
671 * Returns
672 * -ENOMEM: Out of memory.
673 * -EINVAL: Invalid range.
674 */
675int ttm_bo_kmap(struct ttm_buffer_object *bo, unsigned long start_page,
676 unsigned long num_pages, struct ttm_bo_kmap_obj *map);
677
678/**
679 * ttm_bo_kunmap
680 *
681 * @map: Object describing the map to unmap.
682 *
683 * Unmaps a kernel map set up by ttm_bo_kmap.
684 */
685void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
686
687/**
688 * ttm_fbdev_mmap - mmap fbdev memory backed by a ttm buffer object.
689 *
690 * @vma: vma as input from the fbdev mmap method.
691 * @bo: The bo backing the address space. The address space will
692 * have the same size as the bo, and start at offset 0.
693 *
694 * This function is intended to be called by the fbdev mmap method
695 * if the fbdev address space is to be backed by a bo.
696 */
697int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo);
698
699/**
700 * ttm_bo_mmap - mmap out of the ttm device address space.
701 *
702 * @filp: filp as input from the mmap method.
703 * @vma: vma as input from the mmap method.
704 * @bdev: Pointer to the ttm_bo_device with the address space manager.
705 *
706 * This function is intended to be called by the device mmap method.
707 * if the device address space is to be backed by the bo manager.
708 */
709int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
710 struct ttm_bo_device *bdev);
711
712void *ttm_kmap_atomic_prot(struct page *page, pgprot_t prot);
713
714void ttm_kunmap_atomic_prot(void *addr, pgprot_t prot);
715
716/**
717 * ttm_bo_io
718 *
719 * @bdev: Pointer to the struct ttm_bo_device.
720 * @filp: Pointer to the struct file attempting to read / write.
721 * @wbuf: User-space pointer to address of buffer to write. NULL on read.
722 * @rbuf: User-space pointer to address of buffer to read into.
723 * Null on write.
724 * @count: Number of bytes to read / write.
725 * @f_pos: Pointer to current file position.
726 * @write: 1 for read, 0 for write.
727 *
728 * This function implements read / write into ttm buffer objects, and is
729 * intended to
730 * be called from the fops::read and fops::write method.
731 * Returns:
732 * See man (2) write, man(2) read. In particular,
733 * the function may return -ERESTARTSYS if
734 * interrupted by a signal.
735 */
736ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
737 const char __user *wbuf, char __user *rbuf,
738 size_t count, loff_t *f_pos, bool write);
739
740int ttm_bo_swapout(struct ttm_bo_global *glob,
741 struct ttm_operation_ctx *ctx);
742void ttm_bo_swapout_all(struct ttm_bo_device *bdev);
743int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo);
744#endif